Motor-controller.



W. 1). POMEROY.

MOTOR GONTRQLLER, 7

APPLICATION FILED DEC. 31, 1806.

Patented Oct. 27, 1908.

. wood, in the county of Ohio, have invented certain new and use- UNITED sTA'rEs PATENT oFFIoE.

WILLIAM .D. POMEROY, OF N ORW OOD, 'OHIO, ASSIGNOR TO .ALLIS-GHALMEBS COMPANY, A CORPORATION OF N EW JER-SEYYAN D THE BULLOCK ELECTRIC MANUFACTURING GOM- PANY, A CORPORATION OF OHIO.

MOTOR-CONTROLLER,-

Specification of Letters Patent.

Patented Oct. 27, 1908.

Application filed December 31, 1906. serial No. 350,255.

To all whom it may concern:

Be it known'that I, WILLIAM D. POMEROY, citizen of the United States, residing at Norof. Hamilton and State ful Improvements in Motor-Controllers, of which the following is a'full, act specification.

- My invention relates to multiple-voltage controllers.

In the patent to Dunn N 0. 797,271, grantedAug. 15, 1905, there is described a multiple-voltage controller in which a fixed resist ance is temporarily out into the armature mature are changed from one set of mains to another.

known as a buffer resistance, serves to pre-v circuit Whenever the connections of the arhis resistance, now commonly vent excessive surges of current through the armature when the impressed voltagetherev on is either increased or decreased. In the Dunn patent th s buffer resistance is inserted gers from the controller drum, thereby openinga short-circuit around the resistance. This is found to the double movementof the drum and the finger and because'there is only a point or line contact between the finger and its cooperating contact segment on the drum. T he present invention is intended to over- COIHQtlllS diflicu-lty by having the buffer re sistance inserted by a switch separate from the controller drum and-its lingers, but oper ated by the drum in its rotation.

.In one aspect my invention comprises a controller consisting of a rotatable drum,

1 and switch arranged to be 0' ened by said drum. when. the latter is movec between certa n positions, together with means which tends to close said switch and friction mechanism for retarding such closing.

-' In a more specific aspect my invention comprises, in combination, a multiple voltage controller, a motor controlled thereby,

a resistancein the armature circuit of said '.motor, a switch normally closed to shortcircuit said resistance, said switch being sepa- 1 rate from the controller drum, and arranged '50 circuit whenever the ar' {to be opened'thereby tobreak such shortature connections I are changed from one set of mains to another,

clear, and excircuit byrraising one of the contact fin contact fingers f-H to be unsatisfactory, because of spring tends I and friction mechanism for retarding the of said switch.

closing movement of my invention Will ap- Other features pear hereinafter. I

Figure is an elevation of a part of a controller embodying my invention, with the casing partly broken away in order'to show the operating mechanisi'n. Fig. 2 is a section on the line 2-2 of Fig. 1. Fig. 3 is a diagramn'iatic view showing a development of the controller.

In the-drawings, 31 is the controller drum operable by the usual hani'lle 32. 9 For the.

sake of simplicity the connections of the controller drum here indicated. are approximately the same as in the patent to Dunn aforesaid, but it is obvious that my invcntion is applicable to any other form of controller in which the voltage impressed on a motor armature is varied, and especially applicable to any form of multiple-voltage controller. The controller drum has contact segments 33 arranged to cooperate with the the armature oi" motor the mains (1, 1. and d. The drum also has a ring it) and Contact segments 41arra nged to cooperate with contact fingers42 to 48 inclusive to vary the resistance rin the field circuit ol' motor M.

.\lou i it'c(l on the shaft of the controller drum is a cam wheel 49, on the periphery of which rides a roller 50 carried. by'a lever 51. The cam wheel 49 isshown developed in 'Fig. 3, but in order to show more clearly the operation-of the device, projections were on its upper surface instead of on its periphery. These cani projections are so located that they engage with and move roller 50 as the armature connections are being changed from one set of mains to another. The lever 51 switch 52 by a rod 53 is connected to a and a link 54. A; to close the switch 52 and hold it closed. The bar 53'is provided with teeth 56 to former rack, some of these teeth being cut away at 57 for a purpose hereafter explained. -Arranged to engage with the teeth 56 is a pinion 58. Integral with the pinion 58 or otherwise firmly attached thereto is a. friction wheel or disk 59. A

39 inclusive, to connect M to diflerent sets of I it is shown as if its cam band 60 ext-ends around the wheel 59, one .7

v at

end of this band being attached to the contnoller casing through a springGl, while the other end is adjustably attached to said casing'by an adjusting screw 62. By means of {the screw 62 the'friction between the wheel or disk 59 and the band 60 may be ad'usted.

The friction mechanism retards on y' the closing movement of the switch 52, its movemerit in the other direction being practically free or unretarded because the spring 61 l'stretches to loosen the band 60. The switch 52 when closed short-circuits a resistance R in the motor armature circuit, but when opened breaks the short-circuit to effectively include the resistance in said armature circuit.

. When the controller is moved to change the armature connections from one set of mains to another, the cam projections on cam wheel 49 move lever 51 to open the .switch 52 and to include the resistance R in the motor armature circuit. During this opening movement of the switch the teeth of rack 56 enga e with those of pinion 58 to 2E rotate the wheels 58 and 59. T e spring 61 is stretched by this turning, thus so diminishing the friction between the wheel 59 and the band 60 that this opening movement of the switch 52 is not retarded. As soon as the change in the armature connections has been made, the spring 55 begins to expand to force the switch 52 toward closed position. This movement of the switch, however, is at first.

retardedby the bandbrake,-the amount of I this retardation depending upon the adjustment of the screw 62. When the switch is hearlyclosed, the teeth 56 pass out of engageinentrwi'th the pinion 58,- bringing the cutawayportion 57 of the rod 53 adjacent said pinion. This allows the final closing move- "ment of switch 52 to be unretarded so that a quick engagement of the switch contacts may be secured.

In the controller shown the resistance R is included in circuit when the controller passes between positions 7 and 8, 14 and 15, 18 and 19, 21 and 22, and 23 and 24, and also when it passes to or from oil position. Between 'the positions just mentioned the armature connections are changed from one set of mains to another. Between any other two adjacent positions the controller merely varies the resistance 1' in the field circuit of the motor. This field resistance is arranged to be increased as the controller is moved forward between those adjacent positions where the armature connections are not varied, thus increasing the speed of the motor, but to 6 'tui'e; connections are varied, thus insuring a tbtrong field whenever a high voltage is impressed on the armature. v "Itdesired, instead of having some of the teeth on the rack 56 cut away, there maybe other means for preventing the retardation be cut out whenever the armaof the last part of the closing movement of the switch. Also, any desired additional means maybe used to'assist in making the opening movement'of thejswitch52 unret'arded".

It is obvious that the part of the controller which controls the field resistance may be varied as desired, and that the part which controls the armature connections may be adapted to any multiple -"voltage system and arranged if desired to reverse the armature current. These modifications as well as many others which-readily occur to one skilled in the artmay be made without departing from the spirit of my invention, and are intended to be coveredby the claims.

Whatl claim as new-is: v

1. In a controller, a rotatable .drum, a switch biased toward .closed position but arranged to be opened by said drum when the latter is moved between certain-positions, and a band-brake arranged to retard the closing movement of said switch.

In a controller,- a rotatable drum, a switch arranged to be opened by saiddrum when the latter is moved betweencerta'in positions, means which tends to close said switch, and frictionmechanisni arranged to retard the first part ofthe closing movement of said switch but to allow the last part of the closing movement thereof to be unretarded. i

3. A multiple-voltage controller, amotor controlled thereby, a resistance in the M1I1L- ture circuit of said moto r,,a switch normally closed to short-circuit said resistance, said switch being separate from the controller drum but arranged to be. opened thereby to break said short-circuit whenever the arme ture connections are changed from one set of 10: mains to another, and a friction diskeooperating with a friction band for retarding the,

' closing movement of said switch,the tension of said band being adjustable. I

4. A multiple-voltage controller, a motor 11 controlled thereby, a resistance for the armature circuit of said motor, a switch normally closed to short-circuit said resistance, said switch being separate from the controller drum but arranged to be opened thereby to 11 include said resistance in the armature circuit whenever the armature connections are, changed from one set of mains to another, means tending to close said switch, and adjustable friction mechanism for retarding 12 such closure. v

5. A multiple-voltage controller, a motor controlled thereby, a resistanceforthQ lma ture circuit of said motor, a switch normally closed to shortecircuit saidresistance, said 11 switch being separate from the controller drum but arranged to .be' opened thereby. to,;.. effectively include said resistance in the ;armature circuit whenever the armature connections are changed from one set of mains to 1 movement and all of the opening controlled there-by, ture circuit of said closed to short-circuit said resistance, said switch being separate from the controller drum but arranged to be operated thereby to opensaid shortcircu it whenever the armature connections are changed from one set of mains to another, ,and friction mechanism for retarding part of the closing movement of said switch. 1

7. A multiple-voltage controller, a motor controlled thereby, a resistance in the armature circuit of said motor, a switch normally closed to short-circuit said resistance, said switch being separate from the controller drum but arranged to be operated thereby to open said short-circuit whenever the armature'connections are changed from one set of Whole of the o mains to another, a d friction mechanism arranged to retard the first part of the closing movement of said switch, but to allow .the

ast part of the closing movement and the to be unretar ed.

8. A multiple-voltage controller, a motor ening movement of the switch I controlled thereby, a resistance for the armature circuit of said motor, .a switch normally closed to short-circuit said resistance, said switch being separate from the controller drum but arranged to be opened thereby to include said resistance in the-armature cir wit whenever the armature connections are changed from one set of mains to another, means tending to close said switch, and friction mechanism for retarding such closure while allowing a free opening movement of the switch. e

9. In a motor control system, multiplevoltage mains, a motor, a drum controller for connecting the motor armature to different sets of the mains, a resistance in the armature circuit of the motor, a switch separate from the controller and biased to closed position to short circuit said resistance, means whereby a movement of the controller between certain and friction mechanism for retarding closure of said switch.

In testimony whereof I affix my signature, in the presence of two witnesses.

WILLIAM D. POMEROY.

the

Witnesses:

GEO. B. SoHLEr, FRED J.'KINsEY.

positions opens said switch, 

